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Old 03-01-2018, 01:30 PM   #191
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Lets get back to the point please!

So according to the data in the manual, I would expect the plane to reach 8 g at 740 kmh indicated at 1000 m with the previously mentioned 28% fuel with stick pulled back to the limiter.

740 kmh roughly means 0,6 Mach at that alt. meaning 23 deg AOA commanded by the limiter. This corresponds to about 22 deg\second turn rate, which is about max sustained.

Question is: Does it fly like that or not? If not, why?

Also from the same table, max g at 600 kmh should be roughly 6g with AOA limited to 24 deg (Mach 0.5)
Is 6g available at 600 kmh in DCS?

Next there is a flight envelope figure in the book that shows 8g at 550 kmh (roughly) at a weight of 21400 kg. I would assume that this figure is with the stick pulled back as far as it goes. Limiter override or direct control.

This would correspond to a max instantenous turn performance of 29,5 degrees per second. Does the plane achieve that with the stick limiter override or not?

Please test the following data! (I can't because I'm away from home until saturday)
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Old 03-01-2018, 02:23 PM   #192
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If my memory serves me right, the Su-27 limiter in game does not let you pull beyond 22 degrees of AoA as the speed decreases below M 0,7 and that makes the plane perform worse than expected in the 600 kmh region, where it should have the upper hand against other fighters.

So the main question again: can you pull 6g with the limiter on at 600 kmh or not?
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Old 03-01-2018, 02:25 PM   #193
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Press the Y key, I think you have to hold it down.
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Old 03-01-2018, 02:38 PM   #194
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Quote:
Originally Posted by HWasp View Post
If my memory serves me right, the Su-27 limiter in game does not let you pull beyond 22 degrees of AoA as the speed decreases below M 0,7 and that makes the plane perform worse than expected in the 600 kmh region, where it should have the upper hand against other fighters.

So the main question again: can you pull 6g with the limiter on at 600 kmh or not?
Unfortunately, like you, I'm not where I can run a new test at 1000m altitude. I had done a previous test awhile back at 200 m based on the chart that GG posted and got these results:



So I'm thinking that you might not quite be able to. Fuel at the time was 30%, though. And this is only attainable by pulling thru the limiter (holding down the Y-key).
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Old 03-01-2018, 02:39 PM   #195
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Quote:
Originally Posted by GGTharos View Post
Press the Y key, I think you have to hold it down.
I understand the function of the limiter override and use it frequently. I also use the direct control mode during dogfights.

In direct control the plane is capable of 8 gs at that speed at low weights

I think the values in the manual are without overriding the limiter, since it is not a normal procedure to do so (except the flight envelope chart, that seems to show the raw aerodynamic capabilities)

Also in the limitations section there are different AoA limits for different speeds. In my opinion that means the limiter should set itself to those values.
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Old 03-01-2018, 02:54 PM   #196
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Overriding the AoA limiter in RL is pulling through the force imposed by the mechanism - there's no button like we have, so I basically disagree with your statement

I have seen different G limitations based on speed, but not AoA. Where is that?

I wouldn't be against concluding that limiter override doesn't give you quite enough authority for whatever reason.

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Originally Posted by HWasp View Post
I think the values in the manual are without overriding the limiter, since it is not a normal procedure to do so (except the flight envelope chart, that seems to show the raw aerodynamic capabilities)

Also in the limitations section there are different AoA limits for different speeds. In my opinion that means the limiter should set itself to those values.
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Old 03-01-2018, 02:59 PM   #197
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I´m not sure about your last statement.

There is a switch to disengage the AoA-G limiter ¡n the cockpit.



Maybe i´m wrong but if this is not a switch to turn off the AoA-G limiter, what is the function of the switch?

In the Su-27SK manual also there are a explicit reference about "Turning Off the limiter during acrobatic maneuvers doesnt give any apreciable gain in maneuvrability and is possible to make the plane stall or exceed the load limits"
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Old 03-01-2018, 03:02 PM   #198
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And does it actually operate, or is our button just the stick pull-through?
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Old 03-01-2018, 03:03 PM   #199
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Quote:
Originally Posted by GGTharos View Post
Overriding the AoA limiter in RL is pulling through the force imposed by the mechanism - there's no button like we have, so I basically disagree with your statement

I have seen different G limitations based on speed, but not AoA. Where is that?

I wouldn't be against concluding that limiter override doesn't give you quite enough authority for whatever reason.
There's a section in the manual dealing with various aircraft limitations that states acceptable AoA limits for various Mach #s beyond with you might lose control of the aircraft. I believe that's what he's referencing.
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Old 03-01-2018, 03:15 PM   #200
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I think if there is a switch in the real cckpit for turning off the AoA-G limiter is because it has a real function.

Because people in DCS are mapping the AoA-G limiter On-Off in the stick for comodity doesnt mean that in the real cockpit you must move a switch in the left console, not in the stick. And that switch, as far as i know disables the extra weight moving the stick needed when you are passing the AoA -G limit. But i´m not 100% sure.

I´ve read a document in russian where describes the AoA-G limiter and, with a rude online translation thats the conclusion for me. The extra weight and the opposite movement to the center is turned off with the limiter off. But maybe i´m wrong, im not sure. But the manuals says very clear that the limiter can be turned off.
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